string ="他问,你知道 cba 是什么单词的缩写么？"
print(string)
print('1.删除空格')
print('2.英文标点替换')
print('3.首字母大写')
print('4.退出')
while True:
    option = input("请输入功能选项:\n")
    if option=='1':
        string=string.replace(' ','')
        print(string)
    elif option=='2':
        for i in string:
            if i == ',':
                string =string.replace(',',',')
            elif i == '.':
                string =string.replace('.','。')
            elif i=='?':
                string =string.replace('?','?')
            elif i == '?':
                String=string.replace("'","’")
        string =string
        print(string)
    elif option =='3':
        string =string.upper()
        print(string)
    elif option =='4':
       break